Characterization of tetraethylene glycol passivated iron nanoparticles

Autor(es)

Nunes, Eloiza da Silva ^[1] ; Viali, Wesley Renato ^[1] ; da Silva, Sebastiao William ^[2] ; Huamani Coaquira, Jose Antonio ^[2] ; Garg, Vijayendra Kumar ^[2] ; de Oliveira, Aderbal Carlos ^[2] ; Morais, Paulo Cesar ^{[2, 3]} ; Jafelicci Junior, Miguel ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista, Inst Quim, Dept Quim Fis, Lab Mat Magnet & Coloides, BR-14801970 Araraquara, SP - Brazil

^[2] Univ Brasilia, Inst Fis, Nucleo Fis Aplicada, BR-70910900 Brasilia, DF - Brazil

^[3] Huazhong Univ Sci & Technol, Sch Automat, Wuhan 430074 - Peoples R China

• Tipo de documento: Artigo Científico
• Fonte: Applied Surface Science; v. 315, p. 337-345, OCT 1 2014.
• Citações Web of Science: 3

Resumo

The present study describes the synthesis and characterization of iron@iron oxide nanoparticles produced by passivation of metallic iron in tetraethylene glycol media. Structural and chemical characterizations were performed using transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Mossbauer spectroscopy. Pomegranate-like core@shell nanoparticulate material in the size range of 90-120 nm was obtained. According to quantitative phase analysis using Rietveld structure refinement the synthesized iron oxide was identified as magnetite (Fe3O4) whereas the iron to magnetite mass fractions was found to be 47:53. These findings are in good agreement with the data obtained from Mossbauer and thermal gravimetric analysis (TGA). The XPS data revealed the presence of a surface organic layer with higher hydrocarbon content, possibly due to the tetraethylene glycol thermal degradation correlated with iron oxidation. The room-temperature (300K) saturation magnetization measured for the as-synthesized iron and for the iron-iron oxide were 145 emu g-1 and 131 emu g-1, respectively. The measured saturation magnetizations are in good agreement with data obtained from TEM, XRD and Mossbauer spectroscopy. (C) 2014 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 10/20546-0 - Nanopartículas magnéticas caroço@casca: materiais multifuncionais com propriedades para aplicações tecnológicas
• Beneficiário: Miguel Jafelicci Junior
• Modalidade de apoio: Auxílio à Pesquisa - Regular